The floating bolster style 3 motor trucks (GE FB-3 and EMD HTC) are not suitable for high speed service due to stiff primary suspension (elastomeric/steel "sandwiches) and the high unsprung weight of 3 motors. Lateral (yaw)forces of high magnitude (on account of the overall weight of the vehicle) are transmitted direct to the track structure, which can overturn rails.

The E60 had a short-time rating of approximately 10,000 hp-or in excess of 1500 hp per axle. I recall that instrumented testing revealed that the journal boxes could lock up within the pedestal jaws uder these conditions-thus the account of the truck going "solid."

The new Siemens electrics have many features not present in the AEM-7's such as various safety enhancements (AAR S-580 compliance-among others) and 100% redundancy in the HEP system. A new locomotive warranty (probably of the extended variety) will do wonders for the bottom line of the NEC, too.

_________________"Two wrongs don't make a right, but they make a good excuse."-Thomas Szasz

filmteknik

Post subject: Re: AEM-7s

Posted: Sun Oct 07, 2012 9:04 pm

Joined: Sun Oct 19, 2008 12:58 pmPosts: 1215Location: Chicago USA

Whats the point of any 6 axle unit? More tractive effort at lower speeds, in the case of the F40C in commuter service, faster acceleration!

It's all about weight (on drivers). The six axle unit can weigh up to 50% more so develops greater tractive effort at low speed--over so many miles an hour it makes no difference except that you have that many more tons to drag around which then becomes hindrance. It's also about spreading high current at low speeds among more motors so you have a lower minimum continuous speed.

But acceleration? I'm not so sure about that. Does anyone want to confirm or dispute the assertion that an F40C (C-C) can out accelerate an F40PH (B-B), both having the same engine and both having prime mover-driven HEP?

Steve

Jdelhaye

Post subject: Re: AEM-7s

Posted: Sun Oct 07, 2012 10:55 pm

Joined: Mon Apr 30, 2007 12:45 amPosts: 456Location: Illinois

The F40C has 600 hp per axle, while it is 750 hp (20% higher) per axle on the F40PH.

You tell me which is more likely to have a low speed wheel slip under full throttle acceleration.

There is also the matter of 368,000 lbs. vs. 260,000 lbs. which is why I'd like to hear from someone with real world knowledge.

Steve

Mike Swanson

Post subject: Re: AEM-7s

Posted: Mon Oct 08, 2012 7:11 pm

Joined: Mon Dec 29, 2008 12:05 amPosts: 171Location: Albuquerque, NM

Regarding the remaining electrified mine to power plant operations:

Keep in mind that all of these operations (BM&LP, Deseret Western, And Navajo Mine) have all purchased several of the former NdeM E60C-2s that had been sitting dormant after NdeM failed to complete its electrification plans; few if any had actually been used and all were in good shape when purchased. Given that, I seriously doubt they would want to buy locomotives that were not intended for heavy freight service as the E60C-2s were.

The floating bolster style 3 motor trucks (GE FB-3 and EMD HTC) are not suitable for high speed service due to stiff primary suspension (elastomeric/steel "sandwiches) and the high unsprung weight of 3 motors. Lateral (yaw)forces of high magnitude (on account of the overall weight of the vehicle) are transmitted direct to the track structure, which can overturn rails.

Continuing slightly off topic - and certainly a somewhat vague extra credit question - How did the GG-1 perform - what were it's strengths and weaknesses in regards to it's 2-C+C-2 wheel arrangement and motor locations? What was it's top speed - it's recorded top speed on the Corridor? And I suppose, in a related question, the wheel arrangement of the AEM-7, a "Bo-bo" format.

NH0401 wrote:

The new Siemens electrics have many features not present in the AEM-7's such as various safety enhancements (AAR S-580 compliance-among others) and 100% redundancy in the HEP system. A new locomotive warranty (probably of the extended variety) will do wonders for the bottom line of the NEC, too.

Thanks for your insight - seems you hit the nail on the proverbial coffin. New engines would likely be lower cost then keeping upgraded older engines running which would likely need a lot of maintenance and out of warranty work.

/Mitch

K.R. Bell

Post subject: Re: AEM-7s

Posted: Tue Oct 09, 2012 10:22 pm

Joined: Sun Aug 22, 2004 7:37 pmPosts: 217

Does anybody recall if TRAINS Magazine has ever done a feature article on Amtrak AEM-7's?

Does anybody recall if TRAINS Magazine has ever done a feature article on Amtrak AEM-7's?

They haven't. The closest I can find is a 2003 article on Wilmington, Bear, and Beech Grove.

I would dare to say that articles that intensely focused on one particular model or type of locomotive--something Trains used to do quite well, mind you--died out along with the influence of David P. Morgan and J. David Ingles. Mind you, in the British rail enthusiast press, there have been several articles, and even two-part articles--on certain classes of locomotives (the most recent: "50 Years of Class 47s" in Railway Magazine). The argument has been made that "shorter attention spans" don't want the all-encompassing articles of that type anymore. I'd love to be proven wrong.

NH0401

Post subject: Re: AEM-7s

Posted: Wed Oct 10, 2012 9:19 am

Joined: Thu Jan 12, 2006 10:10 pmPosts: 670Location: Iron City

Quote:

Continuing slightly off topic - and certainly a somewhat vague extra credit question - How did the GG-1 perform - what were it's strengths and weaknesses in regards to it's 2-C+C-2 wheel arrangement and motor locations? What was it's top speed - it's recorded top speed on the Corridor? And I suppose, in a related question, the wheel arrangement of the AEM-7, a "Bo-bo" format.

Anecdotal evidence suggests that the GG-1 rode and tracked well at speed...no doubt due to a wheel arrangement proven in service underneath the NH EP-3 passenger electrics. Top speed in test was said to be 110 mph.

One might theorize that by the 1950's, the relative complexity (and cost) of GG-1 running gear was seen as obsolete for electric locos of that era were designed with diesel-electric style running gear.

The AEM-7 is indeed Bo-Bo.

Quote:

I would dare to say that articles that intensely focused on one particular model or type of locomotive--something Trains used to do quite well, mind you--died out along with the influence of David P. Morgan and J. David Ingles. Mind you, in the British rail enthusiast press, there have been several articles, and even two-part articles--on certain classes of locomotives (the most recent: "50 Years of Class 47s" in Railway Magazine). The argument has been made that "shorter attention spans" don't want the all-encompassing articles of that type anymore. I'd love to be proven wrong.

This paragraph brings to mind the incisive TRAINS articles written by GE engineer Forman H Craton pertaining to NH electric loco development and other topics. That type of exposition would be all but impossible today on account of the 'non-disclosure' agreements one must sign as a condition of employment.

DPK

_________________"Two wrongs don't make a right, but they make a good excuse."-Thomas Szasz

Amtrak has announced that it plans to retire all the AEM7's and HHP-8's by the end of 2016 when the new "Cities Sprinters" complete delivery. At least one official Amtrak YouTube video claims the old locos will be gone by 2014! http://www.youtube.com/watch?v=oLdCeSa3bdM

Take that with an appropriate grain of salt, however. In spite of the new MP36's delivered to MARC that were supposed to replace all the diesels, MARC is still keeping in service at least two GP39H-2's, and occasionally spotting emergency reserve power (a supposedly retired GP40HW-2 or even Amtrak work locos!) on a "ready to go" standby basis at Odenton and Baltimore Penn Station.

Meanwhile, a bunch of even newer NJ Transit ALP-44 electrics is retired and went to storage over a year ago..........

Bob Davis

Post subject: Re: AEM-7s

Posted: Mon May 13, 2013 2:23 pm

Joined: Sat Aug 28, 2004 3:25 amPosts: 1025

I've been following this discussion because of my interest in electric railways. I noted with interest the comment from one person who didn't know of any museum with extra storage space. That may be an overstatement, but most museums have already preserved more items than can be restored in the lifetime of most of their members. Then there's the poster who brought up the thought of preserving an AEM-7 in running condition: There are definitely no museums with high-voltage AC on their trolley wire, and even if the unit could be modified to run on 600 volts DC, it would take a lot more amperage to run one of these than it does to run an interurban car or a 60-ton freight motor. (And it would probably need an electrical engineer willing to work on a "pro bono" basis to design the mods). This would mean having a preservation spot near an ex-Pennsy or New Haven electric line and some sort of agreement with Amtrak. Not saying it's impossible, but it would probably require a group with considerable political horsepower to pull it off. Meanwhile, in Southern California, we have enough work to do on our Pacific Electric collection to keep us busy, and some of us have never seen an AEM-7 in person (remembering how provincial many railfans are). And---remember previous discussions about getting a GG-1 adapted to run on 600 VDC.....

_________________Bob Davis
Southern California

RCD

Post subject: Re: AEM-7s

Posted: Mon May 13, 2013 2:44 pm

Joined: Fri Oct 24, 2008 9:05 pmPosts: 706Location: MA

AEM-7 played a more criticle role in american railroad history then say a RS3 yet how maney RS3 are being preserved vs. F40PH or GP38s or any number of more relevent locomotives?

Bob Davis

Post subject: Re: AEM-7s

Posted: Mon May 13, 2013 5:05 pm

Joined: Sat Aug 28, 2004 3:25 amPosts: 1025

AEM-7 units (and for that matter GG-1s) were and are restricted to the Northeast Corridor, so having one as an operating exhibit west of Pennsylvania and south of Washington DC is very unlikely. At least the GG-1 spread around the country in the Lionel O-gauge version, so it's not quite so "foreign". Many historic railway groups emphasize the "nostalgia" aspect of their collections, even going so far as to stage "Wild West train robbery" events. Others play up the "ride the streetcars your grandparents rode" theme. To most folks, an AEM-7 is about as quaint as a 1975 Chevy, and although it would appeal to a certain segment of the railfan community, I doubt that the "general public" would find it that interesting. For most of the country, an F40PH would be more relevant as the symbol that Amtrak was here to stay. Regarding RS-3s, as a product of the last old-time locomotive builder, Alco units have a special place in the hearts of many railfans.

AEM-7 played a more criticle role in american railroad history then say a RS3 yet how maney RS3 are being preserved vs. F40PH or GP38s or any number of more relevent locomotives?

The difference is that those diesels you named could be (and were) sold to other railroads and kept in service for as long as spare parts could be found. Not too many short lines have the overhead to run an AEM on, now, are there?Just like why so many more old pickup trucks exist than sedans within the same year of production, it's the pactical stuff that gets used as long as possible.

At the most recent antique car rally at the Baltimore Streetcar Museum, a 1983 Ford Escort station wagon--with Maryland "Historic" tags--put in an appearance. The owner's father had a 60's Ford, and the grandfather a 1940 Ford.

There was a day when no one could fathom why anyone would save a diesel. Later, a Metroliner.

With regards to the "No museum has the room" argument, if the will were there, the means would appear. And who says it HAS to be at an existing museum? There are numerous museums along the Northeast Corridor that don't have rolling stock, or anything but a caboose: Bowie and Perryville, Md., Newark, Del. (defunct local history museum), Christiana, Pa., and others.

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